Stabilized, chemical nickel plating bath

ABSTRACT

A stabilized chemical bath containing a solution of a nickel salt and selenium compounds as stabilizers.

I United States Patent 1151 3,66 1,596

Clauss et a1. [45] May 9, 1972 [54 STABILIZED, CHEMICAL NICKEL 117/160 R PLATING BATH [56] References Cited [72] Inventors: Wolfgang Clauss; Dieter Menz, both of Berlin, Germany UNITED STATES PATENTS [73] Assignee: Schering AG, Berlin, Germany 2,762,723 9/1956 Talmey et a1. ..1 17/130 2,929,742 3/1960 De Minjer et a1. [221 3,234,031 2/1966 Zirngieb1eta1..... [21] App]. No; 33,088 3,492,135 1/1970 Clauss ..106/1 Primary E.\'aminerLorenzo B. Hayes [30] Foreign Application Priority Data Anome), joseph padlon May 22, 1969 Germany ..P 19 26 100.8

[57] ABSTRACT [52] US. Cl. ..106/1, 1 17/130 E, 1 17/130 B, A Stabilized chemical bath containing a Solution f a nicks] 1 17/160 salt and selenium compounds as stabilizers.

[51 Int. Cl ..C23c 3/02 [58] Field of Search 106/1; 117/130, 130 E, 130 B, 5 Claims, No Drawings STABILIZED, CHEMICAL NICKEL PLATING BATH This invention relates to a stabilized reductive nickel bath containing at least one selenium compound as stabilizers.

For the application of metal layers on a variety of base materials, technical processes are being given more and more attention in which the metals are reductively deposited from baths without any external current source. Thusthe deposi tion of nickel by reduction has in recent years found increasing importance, since reductive nickel precipitates are well suited as corrosion protection means or for the improvement of the surface properties of various materials, and also for the production of conductive layers on plastic plates or substrates.

These baths, which contain in solution a nickel salt, a reducing agent, complex formers and other additions, deposit nickel on the base metal or substrate upon contact of the bath with a catalytically active metal surface.

Not only catalytically active metals, but also many inactive metals and even non-conductors after activation, such as by palladium seeds, can be nickel-plated in this manner.

A disadvantage of the bath compositions or reductive nickel baths that have heretofore been known is their low stability, so that they are often discarded after the metal has been once spent.

Additives for the stabilization of these baths are known. Thus there are proposed in German Pat. No. 1,123,174, for this purpose, sulfur compounds, or if traces of sulfur are already present in the solution, compounds which are able to form sulfur compounds in any form with the sulfur present in the solution. These additives, however, may be added only in small quantities, since higher concentrations may greatly reduce the rate of deposition of the metal or even prevent the smooth deposition. Only in a very narrow concentration range, are xanthogenates and lead ions of the proposed stabilizers said to bring about, besides the stabilization, a slight increase of the rate of deposition, which however is not satisfactory for use in the art.

Also, it is known that in US. Pat. No. 2,929,742, selenious acid as an addition to reductive nickel baths is described, with which the rate of deposition of the nickel can be increased. These baths have the disadvantage, however, of decomposing more rapidly than baths which do not contain this addition.

The use of compounds characterized in the present application for the stabilization of reductive copper baths is also already known. French Pat. No. 1,545,227. However, because of the different behavior of these baths, a suggestion for the use of these compounds as stabilizers in reductive nickel baths could not be derived therefrom.

It has now been found that a reductive, aqueous, nickel bath containing a solution of nickel salt, complex formers, buffer substances, reducing agents and possibly wetting and brightening agents, bases or acids, characterized by a content of one or more selenium-containing compounds, in which the selenium has the degree of oxidation of minus one or minus two, possesses a very good stability, which is greater than that of the known baths.

Other essential advantages of this bath consist in that the rate of deposition is very high and that regeneration with suitable concentrates or individual constituents can be effected for an almost unlimited length of time. Due to its good stability, this bath works without any special maintenance and need not be renewed after use.

Moreover, according to the invention, nickel layers of constant thickness can be deposited from the bath. These coatings are very decorative and distinguish themselves by a bright metallic luster.

By the term, degree of oxidation of the selenium in the characterized selenium compounds is understood the socalled oxidation number or change value, i.e., the charge which an atom would possess in a molecule if the latter were composed only of ions.

Suitable selenium compounds with the degree of oxidation minus one are, for example, compounds of the general formula R Se Se R wherein R, and R, are identical or different and signify a univalent metal equivalent or an organic radical.

Suitable selenium compounds with the degree of oxidation minus two" are, for example, compounds of the general formula RI] Se R g wherein R and R' are identical or different and have the same meaning as R and R R representing in addition hydrogen, the radical CN or the radical SO Me, where Me is a univalent metal equivalent.

Other suitable selenium compounds with the degree of oxidation minus two" are, for example, the selenonium compounds of the general formula wherein R,, R" and R are identical or different and designate an organic radical and X designates an acid radical.

As univalent metal equivalents there enter into consideration, for example: Na, K, Ca/2 or Al/3, etc.; as organic radicals there may be mentioned, for example: aliphatic, cycloaliphatic, aromatic, and araliphatic radicals, which may possibly also be substituted and/or interrupted by one or more heteroatoms, such as oxygen or nitrogen and/or one or more heteroatom groups, such as as well as the acryl radical and the CN group.

Substituents for the mentioned organic radicals are, for example, halogen atoms such as chlorine, bromine, etc., hydroxyl radicals, alkyl radicals, such as methyl and ethyl, etc;, aryloxy radicals, such as phenoxy, etc., alkoxy radicals, such as methoxy and ethoxy etc., acyloxy radicals, such as acetoxy etc., the nitro and cyano group, the carboxyl and the sulfonic acid group in free or functionally modified form; e.g., as esters, or as salts, heterocyclic radicals, such as tetrahydrofuryl, sulfolan, etc., as well as the radicals H NCO-NH-CO- Ar NH CO For the selenonium compounds there may be used the usual acid radicals of the onium compounds, e.g., those of the inorganic acids, advantageously of the halogen hydracids.

Compounds to be used according to the invention are, for example, the following (the compounds marked can be used only in alkaline or neutral but not in acid baths A. Selenium compounds with the degree of oxidation minus one e Potassiumdiselenide.

Dipropyl-diselenide.

. Di-n-butyhdiselenide.

Di-n-amyl-diselenidc.

Di-n-hexy1-disclenide,

Din-heptyl-diselenide.

0 II (HO CHz( J HCH2)2S82 Di-(2,3-dihydroxypropyl)diselonide (KO3S-(CHz)3)zS82 Di-(potassiumsulfopropyl)diselenide. (NaO S(OH )4) Se; Di-(sodiumsulfobutyl)diseleuide.

Di-(sodiumsulfo-methyl-propyl)diselenide.

(NaOOCCHz)zS6 g Bis-(sodiumcarboxymethyl)diselenide.

H0 m, (rurcIrFsmK m s. on, nnr-omsmx Potassium p-tolylsolonpropylsulfouatv.

Potassium carboxyphenylsplmpropylsulimmtu.

Potassium pqnethoxypheuylsolmpropylsul 011mo.

Potassium p-methylphenylselonpropylsulfonnto.

Potassium p-bromphenylselenpropylsulfonntv.

Potassium phenoxyethylsoleupropyisulionate.

Potassium sulfolnnselonpropylsulfmmtu.

Bis-(phonoxyethyl) -solonido.

Diphonylsolonioe.

Dibenzylselenide.

Diiurfurylselenide.

Bis-(p-methylphenyl)-selenide.

Bis-(p-nitrophenyD-selenide.

Bis-(3-phenylpropyl)-solenide.

Dipropyl-selenide. Bis-(hydroxyethyl)-selemdo.

Sodiumselenocyanato.

Pomssiumselenocyunato.

0-, por m-Nitrophenylselenocyanatc.

o, mor p-Methylpheuylselenocyanate.

p-Methoxyphenylselenocyanate.

p-Ethylphenylselenocyanate.

p-Ethoxyphenylselenocyanatc.

Sodium 4-cyansclono-phcnylsulfonate.

CzlIsSUCN C"; '(CII2)3S8CN. Clix N l -oomcm-seon o-, mor p-Chlorphenylselenocyauato.

2-nitro-4-ch10rphenylselenooyanato.

p-C arbmethoxyphenylselonoeynnnto.

Ethylselenocymmto.

Butylselenocyanato.

Decylselenoeyanato.

Potassium selencyano-acetntc.

Potassium selencyunpropionic-acotnto. Potassium selencyanundecanic-ncotato. Potassium selencyanpropylsulfonic-acctato. Potassium selencyunothylsulionicncotuto.

Phenoxyethylseienocyanate.

Furt'urylselenocyanate.

Benzylselenocyanate.

Phenylpropylselenocyanate.

p-Nitropheny1selenocyanate.

fl-Naphthylselenooyanate.

Phen lselenoc anate.

SeON Sulfolanselenocyanate.

CH3 Carboxymethyldimethyl-selenonium-bromide.

Se-CH CO0H +131 CH3 CH3\ Phonacyl-dimethyl-selenonium-bromide.

/SeCH (I3 +Bri (HO OCCHz)zSe CH:COO- Dlmethyl-selenotindicarbonic acid. (cgHshse Br- Triethylselenoniumbromide.

Those compounds having are particularly suitable, as they are easy to proportion and are able to produce prolonged stabilization. Reductive nickel baths containing one or more of these compounds are ex- Dimethylbenzylselenonlum-bromide.

'Iribenzylselenoniumchloride.

Triphenylselenoniumchloride.

Tn'-p-tolyselenoniumchloride.

The compounds named and can be prepared by 'methods known in theart, such as described for the various compound classes in Methods of Organic Chemistry," Houben-Weyl, volume 9 (1955), pages 937-947 (Preparation of selenocyanic acids), pages 972-l,002 (Preparation of selenides), page 1,034 (Preparation of selenonium compounds), pages l,086-l,099 v(Preparation of diselenides), pages 1 ,089-1 ,090 (Preparation of selenosulfates).

The additives for stabilizing reductive nickel baths or ordinary composition may be used in concentrations of about 0.0001 g/liter to 0.3 g/liter, preferably from 0.001 to 0.010 g/liter of bath liquid, the compounds being added either alone or mixed with one another. The nickel baths stabilized according to the present invention contain in addition the usual constituents i.e., nickel salts, reducing agents, buffer substances, complexformcrs as well as wetting and brightening agents,

7 etc.

The p11 value of the baths stabilized according to the invention may be in the acid, neutral,'or alkaline range.

The acid baths work preferably in a pH range of to 6, the alkaline in a preferred pH range of 8 to 9.5. Depending on the reducing agent used, lower or higher pH values may be selected.

The adjustment of the desired pH value is effected, if desired, by the addition of suitable bases or acids, such as soda lye -or hydrochloric acid. To maintain the adjusted pH value, common bufier substances, e.g., Na,B O are also added to the bath.

For the reductive deposition of the nickel, reducing agents are used, such as, alkali metal hypophosphite, such as sodium hypophosphite in the acid and alkaline range, or hydrazine, the salts thereof, borazanes or alkali borohydride, preferably sodium borohydride, in the alkaline range. The concentration of the reducing agent used is about 0.01 to 0.5 mollliter.

'As nickel salts, nickel chloride, nickel sulfate and nickel acetate, etc., are used in concentrations of about 0.01 to 0.5

mollliter. v

1n alkaline medium, nickel salts can, as is known, be maintained in solution only by complex formers. For this there enter into consideration, for example, lactic acid, glycocol, sodium acetate, trisodium citrate and triethanolamine, etc.

, Depending on whether 1:1 or 1:2 complexes are formed, suitable concentrations for this are 0.01 to 0.5 moi/liter respectively 0.02 mollliter to-,1.0 mollliter. Higher concentrations are readily possible,'the maximum concentration being the effect of the solubility of the complex former.

According to another embodiment of the invention, the

bath may additionally contain salts of alloy metals, such as water-soluble salts of cobalt. Also, such a bath distinguishes itself by the described advantageous properies andcan be used for the reductive deposition of nickel alloys. With the nickel baths stabilized according to the invention, it is possible to nickel-plate objects of metals, plastics or other materials in a well known manner.

For this purpose, the materials to be nickel-plated are introduced into the designated baths. The deposition is carried out at a bath temperature of about 20 to 95 C until the desired layer thickness is obtained. For the nickel-plating of plastics one selects, advantageously, temperatures below 65 C. To obtain. uniform nickel layers on the materials to be 1 nickel-plated, it is advisable to agitate the bath vigorously.

Non-conductive materials, such as, plastic parts, require pretreatment of their surfaces. This is done in a manner known in itself, such as by chemical roughening with a heated chromic acid-containing sulfuric acid and chemical activation with a tin-ll chloride and a palladium-ll chloride solution or with a modified palladium solution.

on the metal surface or on the properly prepared surfaces of otherwise non-conductive materials begin.

The following'illustrative examples describe some of the nickel baths stabilized according to the invention.

EXAMPLE 1 0.1 moi/liter NiSO '6H O 0.25 mollliter NaHJO -ILO 0.25 Mol/liter trisodium citrate 0.1 mollliter Ns,5,0,-10 ".0

2 mg/Iiter di-(butyU-diselenide pH: 5.0 J

EXAMPLE 2 0.1 mollliter NiSO.-6 11,0 0.25 mollliter Na1-l,PO,-1-l,0 0.25 mollliter trisodium citrate 0.1 mollliter Na,B O .10 11,0 4 mglliter bis-( 4-nitrobenzyl)-d iselenide pH: 5.5

EXAMPLEG 0.130 mollliter NiCl,-6 ,0 0.10 mollliter NaH,PO,H,O 0.30 mollliter trisodium citrate 0.90 mollliter NH Cl 3 mglliter dibenzyl-diselenide pH: 9.0

EXAMPLE 4 0.1 mollliter NiCl,-6 11,0 0.25 mollliter NaH,PO,'H,O 0.20 mollliter succinic acid 0.1 mollliter Na B,0-, 4mg/1iter benzylseleno-acetic' acid pH: 5.0

EXAMPLE 5 0.1 mollliter Niso,-6 14,0 0.15 mollliter NaH,PO,-H,O 0.25 mollliter succinic acid 1 rag/liter diseleno-dipropionic acid pH: 5.5

EXAMPLE 6 0.1 mollliter NiSO,'6 11,0 0.15 mollliter NalhPOgl-LO 0.05 mollliter Na,B,O,-l0 11,0 4 mg/liter diseleno-diacetic acid pH: 5.5

EXAMPLE 7 0.1 moi/liter NiCl,-7 ",0 0.25 moi/liter NaH,PO,-1!,O 0.3 mollliter sodium acetate 0.1 mollliter Na,B.O 'l0 11,0 2mg/liter dibenzyl-selenide pH: 5.5

EXAMPLE 8 0.1 mollliter NiCl '7 ,0 0.1 mollliter NaH,PO,'1*l,0 0.35 mollliter trisodium citrate 1.00 mollliter NH CI 5 mg/liter potassium 4-nitrobenzyl-selenosulfate PH: 8.5

EXAMPLE 9 0.1 moi/liter NiSO,-7 11,0 0.15 mollliter Na1l,PO,-H,O 0.25 mollliter trisodium acetate 0.5 mollliter NlhCl Zmglliter potassium benzylseleno-sulfate pH: 9.0

EXAMPLE l EXAMPLE 18 0.1 m i/lit z 0.1 moi/liter NiSO.-6 11,0

f succmlc acid 0.25 mol/liter trisodium citrate Q ll 1 1 0.1 mol/liter 101,3 0.10 11,0

0.5 mg/hter phenylacetyl-phenyl-selemde 1 Ins/m" i m lh PH: 5.5 selenium-bromide EXAMPLE l1 EXAMPLE 19 0.05 mol/liter NiSO -7 11,0

01 molllim 4 1 5 0.1 mol/liter Nisom 11,0

06 m i/l NIH 0.20 moi/liter NaH,PO,-l-1,O

0.2 mg/hter phenylacetyl-benzyl selenide OJ momma. NaBoflQ :0

P 120 4 mg/litcr phenylacetyl-beta-chlorphenylselenide pH: 8.0 EXAMPLE l2 EXAMPLE 20 0.05 moi/liter NiSO -7 H,O

0.3 mol/liter Na P,O-,'10 H20 3 i 4 0.1 mol/liter NiCl -7 11 o l5 mgfl'ter Sulfopmpyn' 0.3 mollliter sodium acetate selemde 5 mg/liter methyl-phenyl-acetylenc-selenide pH. 12.5 PH is EXAMPLE 13 EXAMPLE 21 0.1 mol/liter NiSO '6 14,0

0.15 mol/liter lactic acid 0.15 mol/lrter N1S0,'6l-l,0

2 mg/liter dimcthyl-carboxy-methyl- 0.15 mol/l1ter NaHJOfl'l O,

selenium bromide 0.4 moi/liter sodium acetate pH: 6.0 l mg/liter di-(potassium sulfopropyl)- diselenide pH: 6.0

EXAMPLE 14 40 What is claimed is: v 1. in an aqueous electroless nickel plating bath containing a 0.15 ml/me, c q source of nickel ions, a complexing agent and a reducing agent 0.15 mollliter lactic acid capable of reducing said ions to metallic nickel on the surface i Naflzppfmo of an object immersed in said bath, the improvement which 2 mg/hter potassmm butylselenosulfate 55 comprlses a stablhzmg agent 1n sa1d.bath 1n an amount sufficient to substantially prevent spontaneous precipitation of nickel inthe absence of said immersed object, said stabilizer EXAMPLE 15 being selected from the group consisting of organic selenium compounds and the selenides, diselenides, selenosulfate and selenocyanates of an alkali metal, the oxidation state of the 0.2 moi/liter NiCl,-7 11,0 selenium being 1 or 2.

8: mmli o g' a z' ts t 2. A nickel-plating bath according to claim 1 wherein said 1110 I61 8 lumaceae l mgmter sodium phenybselenm stabilizer is present at a concentrauon of about 0.0001 to 0.3

propylsulfonate gram per liter. pH: 5.0 3. A nickel-plating bath according to claim 1 wherein said stabilizer is selected from the group consisting of:

potassium-diselenide; EXAMPLE dipropyl diselenide;

di-n-butyl diselenide; so 6 H o di-n-amyl diselenide;

0.15 mollliter Ni 2 ex d 0.4 mol/liter sodium acetate ep em 4 mg/Iiter sodium ethyl-selenopropyldl-(2-3-d1hydroxypropyl)d1selen1de;

H 5 5 Sulfmme di-(potassiumsulfopropyl)diselenide; P di-(potassiumsulfoethyl)diselenide;

di-(sodiumsulfobutyl)diselenide; EXAMPLE 17 bis-(sodiumcarboxymethyl)diselenide;

bis-(potassiumcarboxylethyl)diselenide; bis-(potassiumcarboxypropyl)diselenide;

0.1 mol/liter Na11,1 0,. 11,0 p y dlselemde;

0.35 mol/litcr trisodium citrate di-p-tolyl diselenide;

5 mg/liter dimethxl-phenyl-acetyl-seleniumd1 (p methoxyphenyl)dlselemde' bromide di-(p-nitrophenyl)diselenide; bis-( o-acetylphenyl)diselenide;

di-2,2'-biphenylyl diselenide;

bis-( p-potassiumsulfophenyl)diselenide;

' bis-(p-chlorophenyndiselenide;

bis-( p-carboxyphenyDdiselenide; diseleniumdiacetylurea;

dibenzyl diselenide;

di-( N-phenyl carbamoylmethyD-diselenide; bis-( p-nitrobenzyndiselenidc;

' bis-(p-methylbenzyl)diselenide;

bis#( p-cyanobenzyhdiselenide; bis-(p-carboxybenzyl)diselenide;

bis-( Bbromobenzyl )diselenide; bis-(B-phenylethyl)diselenide;

bis-( 3-hydroxypropyl)diselenide; his-(a-tetrahydrofurylmethyl)diselenide; his-(fl-phenoxycthyl)diaelenide;

bis-( cyclohexyl )diselenide; bis-(cyclopentyl)diselenide; potassiumselenosulfate; p'otassiumbenzylselenosulfate; potassium p-nitrobenzylselenosulfate potassium p-methylbenzylselenosulfate;

\ potassium p-potassium-carboxybenzylselenosulfate;

potassium p-methoxybenzylselenosulfate; potassium p-ethoxybenzylselenosulfate; potassium p-cyanobenzylselenosulfate; potassium p-ethyi-benzylselenosulfate; potassium p-bromobenzylselenosulfate; potassium ethylselenosulfate;

I potassium butylselenosulfate;

' mor p-chlorophenylseleniumacetic acid;

3,4 -dimethylphenylseleniumacetic acid; 2,4-dimethylphenylseleniurnacetic acid; benzylseleniumacetic acid;

cthylseleniumacetic acid;

scleniumdiacetic acid;

' seleniumdiproponic acid;

seleniumdibutyric acid; benzylseleniumbutyric acid; benzylseleniumundecanoic acid; sodium ethylscleniumpropanesulfonate;

bis-(sodium sulfopropyl)selenide; phenylseleniumglycolic acid; sodium phenylseleniumpropanesulfonate; sodium benzylscleniumpropane sulfonate; bis-( phenoxyethyDselenide; diphenylselenide; dibenzylselenide; difurfurylselenide; bis-p-methylphenylselenide; bis-p-nitrophenylselenide; bis-3-phenylpropylselenide; dipropylselenide; bis-( hydroxyethyhselenide; sodiumselenocyanate; potasiumselenocyanate; 0-, por m-nitrophenylselenocyanate; 0-, mor p-methylphenylselenocyanate; p-methoxyphenylselenocyanate; p-ethylphenylselenocyanate; p-ethoxyphenylselenocyanate; sodium 4-cyanoseleno-phenylsulfonate; 0-, mor p-chlorophenyiselenocyanate; 2-nitro-4-chlorophenylselenocyanate; p-carbmethoxyphenylselenocyanate; ethylselenocyanate; butylselenocyanate; decylselenocyanate; potassium selenocyanoacetate; potassium selenocyanopropionate; potassium selenocyanoundecanoate; potassium selenocyanopropanesulfonate; potassium selenocyanoethanesulfonate; phenoxyethylselenocyanate; furfurylselenocyanate; benzylselenocyanate; v phenylpropylselenocyanate; p-nitrophenylselenocyanate; fi-naphthyiselenocyanate; phenylselenocyanate; carboxymethyldimethyl-selenoniumbromide; phenacyl-dimethyl-selenoniumbromide; dimethyl-selenetin dicarboxylic acid; triethylselenonium iodide; tribenzylselenoniumchloride; dimethyl-benzyl-selenoniumbromide; triphenylselenoniumchloride; tri-p-tolylselenoniumchloride. 4 In the method of depositing nickel on a'conductive surface or an activated nonconductive surface by immersing said surface in a bath containing a source of nickel ions, a complexing agent and a reducing agent capable of reducing said ions on a surface, the improvementwhich comprises im- 1 mersing said surface in a bath according to claim 2.

I i i i l IOIIO35 

2. A nickel-plating bath according to claim 1 wherein said stabilizer is present at a concentration of about 0.0001 to 0.3 gram per liter.
 3. A nickel-plating bath according to claim 1 wherein said stabilizer is selected from the group consisting of: potassium-diselenide; dipropyl diselenide; di-n-butyl diselenide; di-n-amyl diselenide; di-n-hexyl diselenide; di-n-heptyl diselenide; di-(2-3-dihydroxypropyl)diselenide; di-(potassiumsulfopropyl)diselenide; di-(potassiumsulfoethyl)diselenide; di-(sodiumsulfobutyl)diselenide; bis-(sodiumcarboxymethyl)diselenide; bis-(potassiumcarboxylethyl)diselenide; bis-(potassiumcarboxypropyl)diselenide; bis-(potassiumcarboxydecyl)diselenide; diphenyl diselenide; di-p-tolyl diselenide; di-(p-methoxyphenyl)diselenide; di-(p-nitrophenyl)diselenide; bis-(o-acetylphenyl)diselenide; di-2,2''-biphenylyl diselenide; bis-(p-potassiumsulfophenyl)diselenide; bis-(p-chlorophenyl)diselenide; bis-(p-carboxyphenyl)diselenide; diseleniumdiacetylurea; dibenzyl diselenide; di-(N-phenyl-carbamoylmethyl)-diselenide; bis-(p-nitrobenzyl)diselenide; bis-(p-methylbenzyl)diselenide; bis-(p-cyanobenzyl)diselenide; bis-(p-carboxybenzyl)diselenide; bis-(B-bromobenzyl)diselenide; bis-( Beta -phenylethyl)diselenide; bis-(3-hydroxypropyl)diselenide; bis-( Alpha -tetrahydrofurylmethyl)diselenide; bis-( Beta -phenoxyethyl)diselenide; bis-(cyclohexyl)diselenide; bis-(cyclopentyl)diselenide; potassiumselenosulfate; potassiumbenzylselenosulfate; potassium p-nitrobenzylselenosulfate potassium p-methylbenzylselenosulfate; potassium p-potassium-carboxybenzylselenosulfate; potassium p-methoxybenzylselenosulfate; potassium p-ethoxybenzylselenosulfate; potassium p-cyanobenzylselenosulfate; potassium p-ethyl-benzylselenosulfate; potassium p-bromobenzylselenosulfate; potassium ethylselenosulfate; potassium butylselenosulfate; potassium octylselenosulfate; potassium dodecylselenosulfate; potassium 1,3-dihydroxypropylselenosulfate; potassium hydroxyethylselenosulfate; potassium phenoxyethylselenosulfate; potassium tetrahydrofurfurylselenosulfate; potassium phenylethylselenosulfate; potassium phenylpropylselenosulfate; potassium 3-hydroxypropylselenosulfate; dipotassium w-carboxyethylselenosulfate; dipotassium w-carboxybutylselenosulfate; dipotassium w-carboxydecylselenosulfate; dipotassium w-sulfoethylselenosulfate; dipotassium w-sulfopropylselenosulfate; potassium cyclopentylselenosulfate; potassium selenide; phenylseleniumacetic acid; o-, m- or p-nitrophenylseleniumacetic acid; o-, m- or p-methoxyphenylseleniumacetic acid; o-, m- or p-chlorophenylseleniumacetic acid; 3,4 -dimethylphenylseleniumacetic acid; 2,4-dimethylphenylseleniumacetic acid; benzylseleniumacetic acid; ethylseleniumacetic acid; seleniumdiacetic acid; seleniumdiproponic acid; seleniumdibutyric acid; benzylseleniumbutyric acid; benzylseleniumundecanoic acid; sodium ethylseleniumpropanesulfonate; bis-(sodium sulfopropyl)selenide; phenylseleniumglycolic acid; sodium phenylseleniumpropanesulfonate; sodium benzylseleniumpropane sulfonate; bis-(phenoxyethyl)selenide; diphenylselenide; dibenzylselenide; difurfurylselenide; bis-p-methylphenylselenide; bis-p-nitrophenylselenide; bis-3-phenylpropylselenide; dipropylselenide; bis-(hydroxyethyl)selenide; sodiumselenocyanate; potassiumselenocYanate; o-, p- or m-nitrophenylselenocyanate; o-, m- or p-methylphenylselenocyanate; p-methoxyphenylselenocyanate; p-ethylphenylselenocyanate; p-ethoxyphenylselenocyanate; sodium 4-cyanoseleno-phenylsulfonate; o-, m- or p-chlorophenylselenocyanate; 2-nitro-4-chlorophenylselenocyanate; p-carbmethoxyphenylselenocyanate; ethylselenocyanate; butylselenocyanate; decylselenocyanate; potassium selenocyanoacetate; potassium selenocyanopropionate; potassium selenocyanoundecanoate; potassium selenocyanopropanesulfonate; potassium selenocyanoethanesulfonate; phenoxyethylselenocyanate; furfurylselenocyanate; benzylselenocyanate; phenylpropylselenocyanate; p-nitrophenylselenocyanate; Beta -naphthylselenocyanate; phenylselenocyanate; carboxymethyldimethyl-selenoniumbromide; phenacyl-dimethyl-selenoniumbromide; dimethyl-selenetin dicarboxylic acid; triethylselenonium iodide; tribenzylselenoniumchloride; dimethyl-benzyl-selenoniumbromide; triphenylselenoniumchloride; tri-p-tolylselenoniumchloride. 4 In the method of depositing nickel on a conductive surface or an activated nonconductive surface by immersing said surface in a bath containing a source of nickel ions, a complexing agent and a reducing agent capable of reducing said ions on a surface, the improvement which comprises immersing said surface in a bath according to claim
 1. 5. In the method of depositing nickel on a conductive surface or an activated nonconductive surface by immersing said surface in a bath containing a source of nickel ions, a complexing agent and a reducing agent capable of reducing said ions on a surface, the improvement which comprises immersing said surface in a bath according to claim
 2. 